Process for depolymerizing waste ethylene terephthalate polyester
US4078143A · kind A · utility
30Cited by
3References
1Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 9, 1976 |
| Grant date | Mar 7, 1978 |
| Priority date | — |
| Expiry date | Jan 9, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/62
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Recovery of ethylene terephthalate polymer from waste material is accomplished by glycolysis of the polyester to form bis-(2-hydroxyethyl)terephthalate for repolymerization. Formation of objectionable diethylene glycol is inhibited when glycolysis is accomplished by heating the polyester in a reaction mixture with bis-(2-hydroxyethyl)terephthalate, ethylene glycol and sodium acetate trihydrate, and water is introduced continuously into the reaction mixture during depolymerization of the polyester.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.